In oil and gas production there are operations in which communication between the tubing annulus and tubing is advantageous. For example, in circumstances where there is insufficient reservoir pressure to force hydrocarbons in the production tubing from the reservoir to the surface it is common practice to inject gas from the annulus into the hydrocarbon stream to reduce the density of hydrocarbons. When the density of hydrocarbons is reduced, the reservoir pressure is then able to raise the column of hydrocarbons to surface. Access between the annulus and the production tubing is provided by a gas lift valve.
To prevent disruption to the flow of hydrocarbons and to ensure access is still possible to the wellbore and completion components below, gas lift valves, and similar devices that require communication with the annulus, are housed in side pocket mandrels. A side pocket mandrel is a section of tubing which has a pocket offset from the main production bore.
A number of devices for running the tools, such as gas lift valves, down to the side pocket mandrel are known. These devices, known as kick over tools, allow the valve, for example, to be run into the well and, once in position adjacent to the side pocket, deployed by displacing the leading end of the valve away from the kick over tool's body and into the side pocket entrance.
The displacement is activated by a trigger mechanism. The mandrel is provided with a recess for receiving the trigger mechanism. The trigger recess is positioned such that as long as the trigger is in the recess the kick over tool is positioned correctly relative to the side pocket.
To operate the kick over tool, the kick over tool is run-in to the well passed the trigger mechanism recess. The kick over tool is then pulled back into the recess. This pull also fires the trigger mechanism and kicks the leading end of the valve out from the kick over tool body and towards the side pocket entrance. The kick over tool is then lowered down the well, which in turn lowers the valve and sets it into the side pocket.
However, there are drawbacks associated with conventional kick over tools. For example, if the operator pulls back on the kick over tool and it is not located in the recess, there is the possibility that the trigger will be fired by contact with another part of the mandrel. The tool to be deployed, such as the gas lift valve, then kicks over but will not be positioned correctly relative to the side pocket and will not be able to be deployed in the side pocket.
Furthermore, the gas lift valve, for example, can be damaged as it works its way into the side pocket causing a certain amount of bending force to be applied to the valve as it is lowered in. As a result, the sealing packings on the gas lift valve and indeed sensitive internal components can be damaged.